I found a very beat up very small Razor dirt bike I'm wondering where the throttle wires connect to there's a red and the black one.
The throttle in your photo is not the original throttle so unfortunately, it is not compatible with the bike.
For that version of the Razor MX350 dirt bike, a 4-wire throttle with two orange and two brown wires is needed. This throttle is our item # THR-51 which is available on our Razor MX350 Parts Page. The THR-51 throttle has a cable and connector that will plug directly into the bike's controller so no wire splicing or wire connections will be needed.